2 Low with the new electric front axle CAD

[SnoKing]

Anyone look at what it would take to put a switch in this setup for 2 Low?? Snoking

 

[Ozymandias]

You can sure try it, but maybe there is a BUS involved that tells the Tranfer to not switch to Low because of the open FAD.

Toyota has it that way.

 

[SnoKing]

Maybe John Landry will be along with a wiring diagram of the electrical CAD. Snoking

 

[grabinov]

Yeah I've asked this question of just about everyone and in just about every way I can think of, and never really gotten a good answer. We know the truck knows how and when to lock and unlock the front half shafts, we just don't know how to trick it into doing it in 4WD.

 

[Bob4x4]

it will take some new software to make it happen code free.

Operating ranges are selected with a dash mounted shift selector switch. The shift selector switch provides an input to the Drive Train Control Module (DTCM) to indicate the driver's desire to change operating ranges. The DTCM uses this input, along with the input from the transfer case mounted mode sensor and information from the vehicle's CAN C bus, to determine if a shift is permitted. If the DTCM decides the shift is permitted, the DTCM controls the shift motor, mounted to the exterior of the transfer case, to perform the shift.

 

[SnoKing]

it will take some new software to make it happen code free.

Operating ranges are selected with a dash mounted shift selector switch. The shift selector switch provides an input to the Drive Train Control Module (DTCM) to indicate the driver's desire to change operating ranges. The DTCM uses this input, along with the input from the transfer case mounted mode sensor and information from the vehicle's CAN C bus, to determine if a shift is permitted. If the DTCM decides the shift is permitted, the DTCM controls the shift motor, mounted to the exterior of the transfer case, to perform the shift.

So how many wires do to the electric shift motor? Is the shift motor bi-directional? Is there a 4x4 engaged switch that turns on the dash light once the mechanism has fully moved? A view of the wiring diagram of the front axle would tell a lot. 5148812AC is the part number for the wiring harness. SNOKING

 

[sag2]

My guess is the motor is pulse width modulated so you most likely can not just hit it with power and ground.


View attachment TRANSFER-CASE---AUTOMATIC---DIESEL (1).pdf

 

[SnoKing]

My guess is the motor is pulse width modulated so you most likely can not just hit it with power and ground.


View attachment 93783

Well in the draw it would be a good test to just open the VT/DB lead from the module-drive drive train control. Can you post a picture of the mechanical workings of the CAD. Does the electric motor work against a spring loaded slider? SNOKING

 

[sag2]

Sorry, it just shows removal, no detail. You will have to remove yours to see.

 

[SnoKing]

I just talked to Jason at Posi-lok and they have not look at this yet on the new trucks. He said he would talk to engineering about it. SNOKING

 

[NIsaacs]

If I need 4-low I use it and don't think twice about it. Usually if you need low range the extra traction is needed too. When I haul 15K of cinders out of the pit it's great. The road is steep and washboard from the big trucks. Or to start a load in soft ground or up hill. I use it a lot to backup too.

Nick

 

[gsbrockman]

I *assume* this still applies to us guys with Lowly Tradesman trucks and manual floor shifted transfer cases????

 

[SnoKing]

I *assume* this still applies to us guys with Lowly Tradesman trucks and manual floor shifted transfer cases????

Does your truck have the electric CAD? SNOKING

 

[MLee]

I *assume* this still applies to us guys with Lowly Tradesman trucks and manual floor shifted transfer cases????

I assume that the a fore mentioned trucks have something similar to the electronic gizmo for shifting, even with a shift handle.
Mine is of the older CAD system and I interrupted the vacuum line with on/off switching to keep from engaging the front axle.
Been wondering this when the electronics came on the market.

 

[SnoKing]

So, I found this thread!

https://www.turbodieselregister.com/threads/251624-Hacks?highlight=electric+cad

2013+ 3500's and 2014+ 2500's have the new Electric CAD.

I had BobV's 2 low kit on my 2001.5. I used it all the time on a steep hill in our summer RV park when towing the 5th wheel in.

2 Low and a tight torque converter do not get along well for spotting a trailer, as the amount of torque in low range/first gear wants to overcome the rear brakes. Truck was very jumpy!!!!

SNOKING

 

[SnoKing]

I assume that the a fore mentioned trucks have something similar to the electronic gizmo for shifting, even with a shift handle.
Mine is of the older CAD system and I interrupted the vacuum line with on/off switching to keep from engaging the front axle.
Been wondering this when the electronics came on the market.

On the older system one does not want to just disconnect one line. The vacuum motor is bi-directional and requires vacuum on one side or the other to hold the slide collar engaged or disengaged. BobV's kit use vacuum switches or solenoids that reversed the vacuum signals.

His original tube routing required you to interact with his unit for 4x4 mode. I studied the vacuum routes and set my up so the only time I touch the 2 Low control valve was to have 2 low. In other words it all worked normal 2h, 4H 4L. If I wanted 2L I would shift to 4L and see the 4x4 light come on, plug the control value and the 4x4 went out. Much better in my view. It is all documented in this old post. SNOKING

https://www.turbodieselregister.com/threads/209335-Bob-V-2-low-MOD?highlight=low+kit

 

[gtoli]

I have the ST "Tradesman" trim with the floor shifter. I'm considering Spyntec hubs, I know they're expensive, which should give my 2 low on demand.

 

[SnoKing]

I have the ST "Tradesman" trim with the floor shifter. I'm considering Spyntec hubs, I know they're expensive, which should give my 2 low on demand.

The truck will drive slightly better and get a small increase in MPG. SNOKING

 

[jkalchik]

IIRC, you also eliminate unit bearing hubs in favor of serviceable bearings. Still, for the price of the kit, it's awfully hard to justify in terms of increased MPG and lower maintenance cost. No argument that it can be very tempting.

 

[Bob4x4]

The front axle interlock has 4 wires going to it,ign feed ground and 2 control from the dtcm

the wiring repair kit is Number: 68068630AA